The present invention relates to ratchet screw-drivers and wrenches, and more particularly to a new and useful right angle drive for a ratchet screw-driver wherein longitudinal push-button activated motion drives a screw-driver angularly about an axis perpendicular to the longitudinal push button motion.
Conventional screw-drivers usually have an elongated shank with a flattened screw-driver on one end and a handle on the other end of the shank. Such conventional elongated shank screw-drivers have always been and probably will continue to be the most commonly used form of screw-driver device for turning screws. However, in many applications screws are positioned in structures in such a manner that the screw heads are inaccessible to conventional elongated shank type screw-drivers. For example, adjacent parts or components of a structure closely spaced over the screw head often make it impossible to turn the screw by use of a screw-driver with an elongated shank. Therefore, alternative screw-driver forms have been devised to gain access to such screws. For example, the ratchet screw-driver disclosed in U.S. Pat. No. 2,058,855, issued to J. Chapman, shows a ratchet handle screw-driver with a very short screw-driver shank. The screw-driver is driven by arcuate swinging motion of the handle about the axis of the screw-driver shank. The Chapman and similar devices are useful in applications wherein the space over the screw head might be limited, but they also require a wide ranging open space to the side of the screw to allow for sufficient arcuate swinging motion of the handle of the ratchet screw-driver. Where such space to the side of the screw is available, the Chapman type ratchet screw-drivers are useful. However, in many applications, there is both insufficient room over the top of the screw head for use of an elongated shank type screw-driver and insufficient room to the side of the screw head to allow sufficient swinging motion of a swinging handle type ratchet screw-driver. U.S. Pat. No. 2,406,149, issued to J. Jenni, discloses a right angle drive screw-driver with a reciprocating push-rod drive mechanism for use in such situations. However, the push-rod in the Jenni screw-driver must be rotated to disengage the rack and gear teeth drive mechanism after each push to pull the rod back out; otherwise, the screw-driver shank will be driven in a reverse direction. This drawback in the drive mechanism makes the use of the Jenni device somewhat cumbersome. It is also desirable in some circumstances to have the option of a quick reciprocating push button action to drive a screw while it is loose and to also be able to use the leverage of a swinging handle screw-driver to break loose or tighten screws.